Wireless power transmitter, wireless power receiver, and method for controlling same

Abstract

Disclosed is a method for controlling a wireless power transmitter for transmitting charging power to a wireless power receiver. The control method of the present invention comprises the steps of: adjusting the internal impedance of the wireless power transmitter such that the impedance variation occurring when the wireless power receiver is positioned is set to a second impedance variation different from the first impedance variation; applying detection power for detecting the wireless power receiver; detecting the second impedance variation during the application of the detection power so as to detect the wireless power receiver; and changing the impedance variation occurring when the wireless power receiver is positioned from the second impedance variation to the first impedance variation.

Description

PRIORITY[0001]This application is a National Phase Entry of PCT International Application No. PCT / KR2013 / 006167, which was filed on Jul. 10, 2013, and claims a priority to Korean Patent Application No. 10-2012-0075098, which was filed on Jul. 10, 2012, the contents of each of which are incorporated herein by reference.TECHNICAL FIELD[0002]The present invention relates to a wireless power transmitter, a wireless power receiver, and control methods thereof and, more particularly, to a wireless power transmitter, a wireless power receiver, and control methods thereof which can wirelessly transmit / receive charging power.BACKGROUND ART[0003]Mobile terminals such as mobile phones, Personal Digital Assistants (PDAs) and the like are powered by rechargeable batteries. The battery of the mobile terminal is charged with electrical energy by a separate charging device. Typically, a separate contact terminal is formed on the outer side of each of the charging device and the battery, and the cha...

AI Technical Summary

Benefits of technology

[0020]According to various embodiments of the present invention, methods are provided in which a wireless power transmitter detects a wireless power receiver on the basis of an impedance change. Particularly, a wireless power transmitter, according to an embodiment of the present invention, may be designed such that an impedance change in the case of placing a wireless power receiver is large during a period for detecting the wireless power receiver. Also, when transmitting charging power, the wireless power transmitter, according to an embodiment of the present invention, may increase the charging power transmission efficiency by readjusting an impedance. Further, a wireless power receiver, according to an embodiment of the present invention, may be designed such that an impedance change in the case of placing the wireless power receiver is large during a period for detecting the wireless power receiver. In addition, when receiving charging power, the wireless power receiver, according to an embodiment of the present invention, may increase the charging power transmission efficiency by readjusting an impedance.

Problems solved by technology

However, in such a contact-type charging scheme, the contact terminals protrude outwardly, and thus are easily contaminated by foreign substances.

As a result, battery charging is not correctly performed.

Further, battery charging may not be correctly performed when the contact terminals are exposed to moisture.

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